MARK WEST ESTATES
California - Community Water System - PWSID: CA4900800
System Information
| PWSID | CA4900800 |
| System Name | MARK WEST ESTATES |
| System Type | Community Water System |
| Water Source | Ground Water |
| Activity Status | Non-Inventory |
| Owner Type | Private |
| EPA Region | 09 |
| Serves School | No |
| Wholesaler | No |
| First Reported | Mar 22, 1979 |
| Last Reported | Jun 22, 2026 |
Location & Contact
| State | California |
| City | San Rafael |
| ZIP Code | 94903 |
| Address | 155 Esmeyer Drive |
| Organization | Mark West Estates |
| Phone | 4154797206 |
Population & Service
| Population Served | 60 |
| Service Connections | 47 |
Drinking Water Violations (18)
This water system has 18 violations recorded in the EPA SDWIS database.
| Begin Date | End Date | Contaminant | Category | Health-Based | Major | Measured | Federal MCL | State MCL | Status | Return to Compliance | Rule |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Jan 1, 2006 | Dec 31, 2006 | MR | No | Yes | - | 10 mg/L | - | Resolved | Dec 31, 2006 | - | |
| Jan 1, 2006 | Dec 31, 2006 | MR | No | Yes | - | 10 mg/L | - | Resolved | Dec 31, 2006 | - | |
| Jan 1, 2005 | Dec 31, 2005 | MR | No | Yes | - | 0.080 mg/L | - | Resolved | Dec 31, 2005 | - | |
| Jan 1, 2005 | Dec 31, 2005 | MR | No | Yes | - | 0.060 mg/L | - | Resolved | Dec 31, 2005 | - | |
| Jun 30, 1997 | Oct 15, 1997 | MR | No | No | - | 5% of samples | - | Resolved | Oct 15, 1997 | - | |
| Jun 30, 1997 | Oct 15, 1997 | MR | No | No | - | 5% of samples | - | Resolved | Oct 15, 1997 | - | |
| Oct 1, 1996 | Oct 31, 1996 | MCL | Yes | No | - | 5% of samples | - | Archived | Oct 31, 1996 | - | |
| Jul 1, 1996 | Jul 31, 1996 | MR | No | No | - | 5% of samples | - | Resolved | Jul 31, 1996 | - | |
| Jul 1, 1996 | Jul 31, 1996 | MR | No | No | - | 5% of samples | - | Resolved | Jul 31, 1996 | - | |
| Jan 1, 1996 | Feb 10, 1996 | MR | No | No | - | 5% of samples | - | Resolved | Feb 10, 1996 | - | |
| Jan 1, 1996 | Feb 10, 1996 | MR | No | No | - | 5% of samples | - | Resolved | Feb 10, 1996 | - | |
| Sep 1, 1995 | Sep 30, 1995 | MR | No | No | - | 5% of samples | - | Resolved | Sep 30, 1995 | - | |
| Sep 1, 1995 | Sep 30, 1995 | MCL | Yes | No | - | 5% of samples | - | Resolved | Sep 30, 1995 | - | |
| Jul 1, 1993 | Dec 31, 2003 | MR | No | No | - | TT | - | Resolved | Dec 31, 2003 | - | |
| Aug 1, 1984 | Aug 31, 1984 | Other | No | No | - | - | - | Archived | Aug 31, 1984 | - | |
| - | - | - | No | No | - | - | - | - | - | - | |
| - | - | - | No | No | - | - | - | - | - | - | |
| - | - | - | No | No | - | - | - | - | - | - |
About This Water System
Public water system data comes from the EPA Safe Drinking Water Information System (SDWIS). Systems with violations must notify customers. Contact your water utility for the latest annual water quality report.